1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
|
/* Wrapper implementation for waitpid for GNU/Linux (LWP layer).
Copyright (C) 2001-2015 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "common-defs.h"
#ifdef GDBSERVER
/* FIXME: server.h is required for the definition of debug_threads
which is used in the gdbserver-specific debug printing in
linux_debug. This code should be made available to GDB also,
but the lack of a suitable flag to enable it prevents this. */
#include "server.h"
#endif
#include "linux-nat.h"
#include "linux-waitpid.h"
#include "gdb_wait.h"
/* Print debugging output based on the format string FORMAT and
its parameters. */
static inline void
linux_debug (const char *format, ...)
{
#ifdef GDBSERVER
if (debug_threads)
{
va_list args;
va_start (args, format);
vfprintf (stderr, format, args);
va_end (args);
}
#endif
}
/* Convert wait status STATUS to a string. Used for printing debug
messages only. */
char *
status_to_str (int status)
{
static char buf[64];
if (WIFSTOPPED (status))
{
if (WSTOPSIG (status) == SYSCALL_SIGTRAP)
snprintf (buf, sizeof (buf), "%s (stopped at syscall)",
strsignal (SIGTRAP));
else
snprintf (buf, sizeof (buf), "%s (stopped)",
strsignal (WSTOPSIG (status)));
}
else if (WIFSIGNALED (status))
snprintf (buf, sizeof (buf), "%s (terminated)",
strsignal (WTERMSIG (status)));
else
snprintf (buf, sizeof (buf), "%d (exited)", WEXITSTATUS (status));
return buf;
}
/* Wrapper function for waitpid which handles EINTR, and emulates
__WALL for systems where that is not available. */
int
my_waitpid (int pid, int *status, int flags)
{
int ret, out_errno;
linux_debug ("my_waitpid (%d, 0x%x)\n", pid, flags);
if (flags & __WALL)
{
sigset_t block_mask, org_mask, wake_mask;
int wnohang;
wnohang = (flags & WNOHANG) != 0;
flags &= ~(__WALL | __WCLONE);
if (!wnohang)
{
flags |= WNOHANG;
/* Block all signals while here. This avoids knowing about
LinuxThread's signals. */
sigfillset (&block_mask);
sigprocmask (SIG_BLOCK, &block_mask, &org_mask);
/* ... except during the sigsuspend below. */
sigemptyset (&wake_mask);
}
while (1)
{
/* Since all signals are blocked, there's no need to check
for EINTR here. */
ret = waitpid (pid, status, flags);
out_errno = errno;
if (ret == -1 && out_errno != ECHILD)
break;
else if (ret > 0)
break;
if (flags & __WCLONE)
{
/* We've tried both flavors now. If WNOHANG is set,
there's nothing else to do, just bail out. */
if (wnohang)
break;
linux_debug ("blocking\n");
/* Block waiting for signals. */
sigsuspend (&wake_mask);
}
flags ^= __WCLONE;
}
if (!wnohang)
sigprocmask (SIG_SETMASK, &org_mask, NULL);
}
else
{
do
ret = waitpid (pid, status, flags);
while (ret == -1 && errno == EINTR);
out_errno = errno;
}
linux_debug ("my_waitpid (%d, 0x%x): status(%x), %d\n",
pid, flags, status ? *status : -1, ret);
errno = out_errno;
return ret;
}
|
